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The aberrant expression of specific long noncoding RNAs (lncRNAs) has been associated with cognitive and psychiatric disorders. Although a growing number of lncRNAs are now known to regulate neural cell development and function, relatively few lncRNAs have been shown to underlie animal behavior. Pnky is an evolutionarily conserved, neural lncRNA that regulates brain development. Using mouse genetic strategies, we show that Pnky has sex-specific roles in mouse behavior and that this lncRNA can underlie specific behavior by functioning in trans. Male Pnky-knockout mice have decreased context generalization in a paradigm of associative fear learning and memory. In female Pnky-knockout mice, there is an increase in the acoustic startle response, a behavior that is altered in affective disorders. Remarkably, expression of Pnky from a bacterial artificial chromosome transgene decreases the acoustic startle response in female Pnky-knockout mice, demonstrating that Pnky can modulate specific animal behavior by functioning in trans. More broadly, these studies illustrate how specific lncRNAs can underlie cognitive and mood disorders.
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Comportamento Animal , Medo , Camundongos Knockout , RNA Longo não Codificante , Reflexo de Sobressalto , Animais , Feminino , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Masculino , Comportamento Animal/fisiologia , Camundongos , Reflexo de Sobressalto/fisiologia , Medo/fisiologia , Memória/fisiologia , Camundongos Endogâmicos C57BL , Fatores SexuaisRESUMO
BACKGROUND: Understanding how SARS-CoV-2 breakthrough infections impacts the breadth of immune responses against existing and pre-emergent SARS-CoV-2 strains is needed to develop an evidence-based long-term immunisation strategy. METHODS: We performed a randomised, controlled trial to assess the immunogenicity of homologous (BNT162b2) versus heterologous (mRNA-1273) booster vaccination in 100 BNT162b2-vaccinated infection-naïve individuals enrolled from October 2021. Post hoc analysis was performed to assess the impact of SARS-CoV-2 infection on humoral and cellular immune responses against wild-type SARS-CoV-2 and/or Omicron subvariants. FINDINGS: 93 participants completed the study at day 360. 71% (66/93) of participants reported first SARS-CoV-2 Omicron infection by the end of the study with similar proportions of infections between homologous and heterologous booster groups (72.3% [34/47] vs 69.6% [32/46]; p = 0.82). Mean wildtype SARS-CoV-2 anti-S-RBD antibody level was significantly higher in heterologous booster group compared with homologous group at day 180 (14,588 IU/mL; 95% CI, 10,186-20,893 vs 7447 IU/mL; 4646-11,912; p = 0.025). Participants who experienced breakthrough infections during the Omicron BA.1/2 wave had significantly higher anti-S-RBD antibody levels against wildtype SARS-CoV-2 and antibody neutralisation against BA.1 and pre-emergent BA.5 compared with infection-naïve participants. Regardless of hybrid immunity status, wildtype SARS-CoV-2 anti-S-RBD antibody level declined significantly after six months post-booster or post-SARS-CoV-2 infection. INTERPRETATION: Booster vaccination with mRNA-1273 was associated with significantly higher antibody levels compared with BNT162b2. Antibody responses are narrower and decline faster among uninfected, vaccinated individuals. Boosters may be more effective if administered shortly before infection outbreaks and at least six months after last infection or booster. FUNDING: Singapore NMRC, USFDA, MRC.
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BACKGROUND: Frailty is an important predictor of health outcomes, characterized by increased vulnerability due to physiological decline. The Clinical Frailty Scale (CFS) is commonly used for frailty assessment but may be influenced by rater bias. Use of artificial intelligence (AI), particularly Large Language Models (LLMs) offers a promising method for efficient and reliable frailty scoring. METHODS: The study utilized seven standardized patient scenarios to evaluate the consistency and reliability of CFS scoring by OpenAI's GPT-3.5-turbo model. Two methods were tested: a basic prompt and an instruction-tuned prompt incorporating CFS definition, a directive for accurate responses, and temperature control. The outputs were compared using the Mann-Whitney U test and Fleiss' Kappa for inter-rater reliability. The outputs were compared with historic human scores of the same scenarios. RESULTS: The LLM's median scores were similar to human raters, with differences of no more than one point. Significant differences in score distributions were observed between the basic and instruction-tuned prompts in five out of seven scenarios. The instruction-tuned prompt showed high inter-rater reliability (Fleiss' Kappa of 0.887) and produced consistent responses in all scenarios. Difficulty in scoring was noted in scenarios with less explicit information on activities of daily living (ADLs). CONCLUSIONS: This study demonstrates the potential of LLMs in consistently scoring clinical frailty with high reliability. It demonstrates that prompt engineering via instruction-tuning can be a simple but effective approach for optimizing LLMs in healthcare applications. The LLM may overestimate frailty scores when less information about ADLs is provided, possibly as it is less subject to implicit assumptions and extrapolation than humans. Future research could explore the integration of LLMs in clinical research and frailty-related outcome prediction.
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The nuclear genome is spatially organized into a three-dimensional (3D) architecture by physical association of large chromosomal domains with subnuclear compartments including the nuclear lamina at the radial periphery and nuclear speckles within the nucleoplasm1-5. However, how spatial genome architecture regulates human brain development has been overlooked owing to technical limitations. Here, we generate high-resolution maps of genomic interactions with the lamina and speckles in cells of the neurogenic lineage isolated from midgestational human cortex, uncovering an intimate association between subnuclear genome compartmentalization, chromatin state and transcription. During cortical neurogenesis, spatial genome organization is extensively remodeled, relocating hundreds of neuronal genes from the lamina to speckles including key neurodevelopmental genes bivalent for H3K27me3 and H3K4me3. At the lamina, bivalent genes have exceptionally low expression, and relocation to speckles enhances resolution of bivalent chromatin to H3K4me3 and increases transcription >7-fold. We further demonstrate that proximity to the nuclear periphery - not the presence of H3K27me3 - is the dominant factor in maintaining the lowly expressed, poised state of bivalent genes embedded in the lamina. In addition to uncovering a critical role of subnuclear genome compartmentalization in neurogenic transcriptional regulation, our results establish a new paradigm in which knowing the spatial location of a gene is necessary to understanding its epigenomic regulation.
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BACKGROUND: Discharge letters are a critical component in the continuity of care between specialists and primary care providers. However, these letters are time-consuming to write, underprioritized in comparison to direct clinical care, and are often tasked to junior doctors. Prior studies assessing the quality of discharge summaries written for inpatient hospital admissions show inadequacies in many domains. Large language models such as GPT have the ability to summarize large volumes of unstructured free text such as electronic medical records and have the potential to automate such tasks, providing time savings and consistency in quality. OBJECTIVE: The aim of this study was to assess the performance of GPT-4 in generating discharge letters written from urology specialist outpatient clinics to primary care providers and to compare their quality against letters written by junior clinicians. METHODS: Fictional electronic records were written by physicians simulating 5 common urology outpatient cases with long-term follow-up. Records comprised simulated consultation notes, referral letters and replies, and relevant discharge summaries from inpatient admissions. GPT-4 was tasked to write discharge letters for these cases with a specified target audience of primary care providers who would be continuing the patient's care. Prompts were written for safety, content, and style. Concurrently, junior clinicians were provided with the same case records and instructional prompts. GPT-4 output was assessed for instances of hallucination. A blinded panel of primary care physicians then evaluated the letters using a standardized questionnaire tool. RESULTS: GPT-4 outperformed human counterparts in information provision (mean 4.32, SD 0.95 vs 3.70, SD 1.27; P=.03) and had no instances of hallucination. There were no statistically significant differences in the mean clarity (4.16, SD 0.95 vs 3.68, SD 1.24; P=.12), collegiality (4.36, SD 1.00 vs 3.84, SD 1.22; P=.05), conciseness (3.60, SD 1.12 vs 3.64, SD 1.27; P=.71), follow-up recommendations (4.16, SD 1.03 vs 3.72, SD 1.13; P=.08), and overall satisfaction (3.96, SD 1.14 vs 3.62, SD 1.34; P=.36) between the letters generated by GPT-4 and humans, respectively. CONCLUSIONS: Discharge letters written by GPT-4 had equivalent quality to those written by junior clinicians, without any hallucinations. This study provides a proof of concept that large language models can be useful and safe tools in clinical documentation.
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Alta do Paciente , Humanos , Alta do Paciente/normas , Registros Eletrônicos de Saúde/normas , Método Simples-Cego , IdiomaRESUMO
BACKGROUND: Does experiencing adversity engender kindness, and if so, for whom? Two studies tested the hypothesis that adversity predicts increased pro-social outcomes, and that this relationship is strongest for individuals who view others as good and trustworthy, or benevolent. METHOD: In Study 1, a cross-sectional survey design was utilized, and in Study 2 a longitudinal survey was conducted. RESULTS: In Study 1 (N = 359), the number of lifetime adverse life events was associated with increased volunteering, empathic concern, and self-reported altruism. The association of adversity and altruism was stronger for those with greater benevolence beliefs. In Study 2 (N = 1157), benevolence beliefs were assessed, and in subsequent years, adverse life events were reported. The number of past-year adverse life events predicted more volunteering and charitable involvement, but only among people with high benevolence beliefs. CONCLUSION: Exposure to adversity may be associated with increased pro-social behavior among those with higher benevolence beliefs. In part, this could be due to benevolence beliefs increasing the expectation that one's efforts will be appreciated and reciprocated.
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Neurogenesis and gliogenesis continue in the Ventricular-Subventricular Zone (V-SVZ) of the adult rodent brain. B1 cells are astroglial cells derived from radial glia that function as primary progenitors or neural stem cells (NSCs) in the V-SVZ. B1 cells, which have a small apical contact with the ventricle, decline in numbers during early postnatal life, yet neurogenesis continues into adulthood. Here we found that a second population of V-SVZ astroglial cells (B2 cells), that do not contact the ventricle, function as NSCs in the adult brain. B2 cell numbers increase postnatally, remain constant in 12-month-old mice and decrease by 18 months. Transcriptomic analysis of ventricular-contacting and non-contacting B cells revealed key molecular differences to distinguish B1 from B2 cells. Transplantation and lineage tracing of B2 cells demonstrate their function as primary progenitors for adult neurogenesis. This study reveals how NSC function is relayed from B1 to B2 progenitors to maintain adult neurogenesis.
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Tumors may contain billions of cells, including distinct malignant clones and nonmalignant cell types. Clarifying the evolutionary histories, prevalence, and defining molecular features of these cells is essential for improving clinical outcomes, since intratumoral heterogeneity provides fuel for acquired resistance to targeted therapies. Here we present a statistically motivated strategy for deconstructing intratumoral heterogeneity through multiomic and multiscale analysis of serial tumor sections (MOMA). By combining deep sampling of IDH-mutant astrocytomas with integrative analysis of single-nucleotide variants, copy-number variants, and gene expression, we reconstruct and validate the phylogenies, spatial distributions, and transcriptional profiles of distinct malignant clones. By genotyping nuclei analyzed by single-nucleus RNA-seq for truncal mutations, we further show that commonly used algorithms for identifying cancer cells from single-cell transcriptomes may be inaccurate. We also demonstrate that correlating gene expression with tumor purity in bulk samples can reveal optimal markers of malignant cells and use this approach to identify a core set of genes that are consistently expressed by astrocytoma truncal clones, including AKR1C3, whose expression is associated with poor outcomes in several types of cancer. In summary, MOMA provides a robust and flexible strategy for precisely deconstructing intratumoral heterogeneity and clarifying the core molecular properties of distinct cellular populations in solid tumors.
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AIMS: The role of change in left atrial (LA) parameters prior to the onset of heart failure (HF) remains unclear. We used cardiac magnetic resonance (CMR) imaging to investigate the relationship between longitudinal change in LA function and incident HF in a multi-ethnic population with subclinical cardiovascular disease (CVD). METHODS AND RESULTS: In this prospective multi-ethnic cohort study, 2470 participants (60 ± 9 years, 47% males), free at baseline of clinical CVD, had LA volume and function assessed via multimodality tissue tracking on CMR imaging at baseline (2000-02) and a second study 9.4 ± 0.6 years later. Free of HF, 73 participants developed incident HF [HF with preserved ejection fraction (HFpEF), n = 39; reduced ejection fraction (HFrEF), n = 34] 7.1 ± 2.1 years after the second study. An annual decrease of 1 SD unit in peak LA strain (ΔLASmax) was most strongly associated with the risk of HFpEF [subdistribution hazard ratios (HR) = 2.56, 95% confidence interval (CI) (1.34-4.90), P = 0.004] and improved model reclassification and discrimination in predicting HFpEF [C-statistic = 0.84, 95% CI (0.79-0.90); net reclassification index (NRI) = 0.34, P = 0.01; and integrated discrimination index (IDI) = 0.02, P = 0.02], whilst an annual decrease of 1â mL/m2 of pre-atrial indexed LA volumes (ΔLAVipreA) was most strongly associated with the risk of HFrEF [subdistribution HR = 1.88, 95% CI (1.44-2.45), P < 0.001] and improved model reclassification and discrimination in predicting HFrEF [C-statistic = 0.81, 95% CI (0.72-0.90); NRI = 0.31, P = 0.03; and IDI = 0.01, P = 0.50] after adjusting for event-specific risk factors and baseline LA measures. CONCLUSION: ΔLASmax and ΔLAVipreA were associated with and incrementally predictive of HFpEF and HFrEF, after adjusting for risk factors and baseline LA measures in this population of subclinical CVD.
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Cannabis-related emergency department visits have increased after legalization of cannabis for medical and recreational use. Accordingly, the incidence of emergency department visits due to cannabinoid hyperemesis syndrome in patients with chronic cannabis use has also increased. The aim of this study was to examine trends of emergency department visit due to cannabinoid hyperemesis syndrome in Nevada and evaluate factors associated with the increased risk for emergency department visit. The State Emergency Department Databases of Nevada between 2013 and 2021 were used for investigating trends of emergency department visits for cannabinoid hyperemesis syndrome. We compared patients visiting the emergency department due to cannabinoid hyperemesis syndrome with those visiting the emergency department due to other causes except cannabinoid hyperemesis and estimated the impact of cannabis commercialization for recreational use. Emergency department visits due to cannabinoid hyperemesis syndrome have continuously increased during the study period. The number of emergency department visits per 100,000 was 1.07 before commercialization for recreational use. It increased to 2.22 per 100,000 (by approximately 1.1 per 100,000) after commercialization in the third quarter of 2017. Those with cannabinoid hyperemesis syndrome were younger with fewer male patients than those without cannabinoid hyperemesis syndrome. A substantial increase in emergency department visits due to cannabinoid hyperemesis syndrome occurred in Nevada, especially after the commercialization of recreational cannabis. Further study is needed to explore factors associated with emergency department visits.
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Canabinoides , Serviço Hospitalar de Emergência , Vômito , Humanos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Masculino , Feminino , Adulto , Vômito/induzido quimicamente , Vômito/epidemiologia , Nevada/epidemiologia , Canabinoides/efeitos adversos , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Síndrome , Incidência , Síndrome da Hiperêmese Canabinoide , Visitas ao Pronto SocorroRESUMO
Background: The gluteus minimus (GMin) and gluteus medius (GMed) are important dynamic stabilizers of the hip, but quantitative data on their biomechanical roles in stabilizing the hip are currently lacking. Purpose: To (1) establish a reproducible biomechanical cadaveric model of the hip abductor complex and (2) characterize the effects of loading the GMin and GMed on extraneous femoral rotation and distraction. Study Design: Controlled laboratory study. Methods: A total of 10 hemipelvises were tested in 4 muscle loading states: (1) unloaded, (2) the GMin loaded, (3) the GMed loaded, and (4) both the GMin and GMed loaded. Muscle loads were applied via cables, pulleys, and weights attached to the tendons to replicate the anatomic lines of action. Specimens were tested under internal rotation; external rotation; and axial traction forces at 0°, 15°, 30°, 60°, and 90° of hip flexion. Results: When loaded together, the GMin and GMed reduced internal rotation motion at all hip flexion angles (P < .05) except 60° and reduced external rotation motion at all hip flexion angles (P < .05) except 0°. Likewise, when both the GMin and GMed were loaded, femoral distraction was decreased at all angles of hip flexion (P < .05). Conclusion: The results of this study demonstrated that the GMin and GMed provide stability against rotational torques and distractive forces and that the amount of contribution depends on the degree of hip flexion. Clinical Relevance: Improved understanding of the roles of the GMin and GMed in preventing rotational and distractive instability of the hip will better guide treatment of hip pathologies and optimize nonoperative and operative therapies.
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Background: Socioeconomic status (SES) is a well-established determinant of cardiovascular health. However, the relationship between SES and clinical outcomes in long-term out-of-hospital cardiac arrest (OHCA) is less well-understood. The Singapore Housing Index (SHI) is a validated building-level SES indicator. We investigated whether SES as measured by SHI is associated with long-term OHCA survival in Singapore. Methods: We conducted an open cohort study with linked data from the Singapore Pan-Asian Resuscitation Outcomes Study (PAROS), and the Singapore Registry of Births and Deaths (SRBD) from 2010 to 2020. We fitted generalized structural equation models, calculating hazard ratios (HRs) using a Weibull model. We constructed Kaplan-Meier survival curves and calculated the predicted marginal probability for each SHI category. Results: We included 659 cases. In both univariable and multivariable analyses, SHI did not have a significant association with survival. Indirect pathways of SHI mediated through covariates such as Emergency Medical Services (EMS) response time (HR of low-medium, high-medium and high SHI when compared to low SHI: 0.98 (0.88-1.10), 1.01 (0.93-1.11), 1.02 (0.93-1.12) respectively), and age of arrest (HR of low-medium, high-medium and high SHI when compared to low SHI: 1.02 (0.75-1.38), 1.08 (0.84-1.38), 1.18 (0.91-1.54) respectively) had no significant association with OHCA survival. There was no clear trend in the predicted marginal probability of survival among the different SHI categories. Conclusions: We did not find a significant association between SES and OHCA survival outcomes in residential areas in Singapore. Among other reasons, this could be due to affordable healthcare across different socioeconomic classes.
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Mechanisms specifying cancer cell states and response to therapy are incompletely understood. Here we show epigenetic reprogramming shapes the cellular landscape of schwannomas, the most common tumors of the peripheral nervous system. We find schwannomas are comprised of 2 molecular groups that are distinguished by activation of neural crest or nerve injury pathways that specify tumor cell states and the architecture of the tumor immune microenvironment. Moreover, we find radiotherapy is sufficient for interconversion of neural crest schwannomas to immune-enriched schwannomas through epigenetic and metabolic reprogramming. To define mechanisms underlying schwannoma groups, we develop a technique for simultaneous interrogation of chromatin accessibility and gene expression coupled with genetic and therapeutic perturbations in single-nuclei. Our results elucidate a framework for understanding epigenetic drivers of tumor evolution and establish a paradigm of epigenetic and metabolic reprograming of cancer cells that shapes the immune microenvironment in response to radiotherapy.
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Neurilemoma , Humanos , Neurilemoma/genética , Neurilemoma/patologia , Epigênese Genética , Reprogramação Celular/genética , Microambiente Tumoral/genéticaRESUMO
BACKGROUND AND AIM: Colonoscopy is commonly used in screening and surveillance for colorectal cancer. Multiple different guidelines provide recommendations on the interval between colonoscopies. This can be challenging for non-specialist healthcare providers to navigate. Large language models like ChatGPT are a potential tool for parsing patient histories and providing advice. However, the standard GPT model is not designed for medical use and can hallucinate. One way to overcome these challenges is to provide contextual information with medical guidelines to help the model respond accurately to queries. Our study compares the standard GPT4 against a contextualized model provided with relevant screening guidelines. We evaluated whether the models could provide correct advice for screening and surveillance intervals for colonoscopy. METHODS: Relevant guidelines pertaining to colorectal cancer screening and surveillance were formulated into a knowledge base for GPT. We tested 62 example case scenarios (three times each) on standard GPT4 and on a contextualized model with the knowledge base. RESULTS: The contextualized GPT4 model outperformed the standard GPT4 in all domains. No high-risk features were missed, and only two cases had hallucination of additional high-risk features. A correct interval to colonoscopy was provided in the majority of cases. Guidelines were appropriately cited in almost all cases. CONCLUSIONS: A contextualized GPT4 model could identify high-risk features and quote appropriate guidelines without significant hallucination. It gave a correct interval to the next colonoscopy in the majority of cases. This provides proof of concept that ChatGPT with appropriate refinement can serve as an accurate physician assistant.
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Colonoscopia , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/epidemiologia , Fatores de Risco , Detecção Precoce de Câncer , AlucinaçõesRESUMO
BACKGROUND: To enhance perioperative outcomes, a perioperative registry that integrates high-quality real-world data throughout the perioperative period is essential. Singapore General Hospital established the Perioperative and Anesthesia Subject Area Registry (PASAR) to unify data from the preoperative, intraoperative, and postoperative stages. This study presents the methodology employed to create this database. METHODS: Since 2016, data from surgical patients have been collected from the hospital electronic medical record systems, de-identified, and stored securely in compliance with privacy and data protection laws. As a representative sample, data from initiation in 2016 to December 2022 were collected. RESULTS: As of December 2022, PASAR data comprise 26 tables, encompassing 153,312 patient admissions and 168,977 operation sessions. For this period, the median age of the patients was 60.0 years, sex distribution was balanced, and the majority were Chinese. Hypertension and cardiovascular comorbidities were also prevalent. Information including operation type and time, intensive care unit (ICU) length of stay, and 30-day and 1-year mortality rates were collected. Emergency surgeries resulted in longer ICU stays, but shorter operation times than elective surgeries. CONCLUSIONS: The PASAR provides a comprehensive and automated approach to gathering high-quality perioperative patient data.
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Anestesia , Data Warehousing , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Eletivos , Admissão do Paciente , Sistema de RegistrosRESUMO
Recent clinical trials for H3K27-altered diffuse midline gliomas (DMGs) have shown much promise. We present a consensus roadmap and identify three major barriers: (1) refinement of experimental models to include immune and brain-specific components; (2) collaboration among researchers, clinicians, and industry to integrate patient-derived data through sharing, transparency, and regulatory considerations; and (3) streamlining clinical efforts including biopsy, CNS-drug delivery, endpoint determination, and response monitoring. We highlight the importance of comprehensive collaboration to advance the understanding, diagnostics, and therapeutics for DMGs.
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Neoplasias Encefálicas , Glioma , Humanos , Criança , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/diagnóstico , Glioma/genética , Glioma/terapia , Mutação , Encéfalo/patologia , BiópsiaRESUMO
The uncertain future due to the COVID-19 pandemic and the technological advancements may have altered young adults' experiences of romantic relationships. It is unclear whether individuals will continue to prefer traditional long-term romantic relationships (LTRR) or opt for short-term ones (STRR). This research describes how young adults in Malaysia perceive LTRR and STRR. Using the structured approach of the theory of social representations, data were collected from 512 participants; 238 (46.48%) male; Mage 21.75; majority were heterosexual and students, and analyzed using prototypical analysis to reveal high consensus elements. Five observations were made: (1) females prioritize "love" in both STRR and LTRR, while males prioritize "love" only in LTRR; (2) females prioritize "marriage" in LTRR, while males prioritize "trust," "comfort," and "stability." Males do not consider "marriage" as part of a LTRR; (3) both males and females view STRR positively, while LTRR are viewed more practically; (4) "sex" is a core element in STRR but is absent in LTRR; (5) males differentiate between STRR and LTRR with no overlapping elements. These findings provide insight into the social representations of romantic relationships among young adults in Malaysia and suggest future directions for research in the field.
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Relações Interpessoais , Pandemias , Feminino , Humanos , Masculino , Adulto Jovem , Adulto , MalásiaRESUMO
Tumors may contain billions of cells including distinct malignant clones and nonmalignant cell types. Clarifying the evolutionary histories, prevalence, and defining molecular features of these cells is essential for improving clinical outcomes, since intratumoral heterogeneity provides fuel for acquired resistance to targeted therapies. Here we present a statistically motivated strategy for deconstructing intratumoral heterogeneity through multiomic and multiscale analysis of serial tumor sections (MOMA). By combining deep sampling of IDH-mutant astrocytomas with integrative analysis of single-nucleotide variants, copy-number variants, and gene expression, we reconstruct and validate the phylogenies, spatial distributions, and transcriptional profiles of distinct malignant clones. By genotyping nuclei analyzed by single-nucleus RNA-seq for truncal mutations, we further show that commonly used algorithms for identifying cancer cells from single-cell transcriptomes may be inaccurate. We also demonstrate that correlating gene expression with tumor purity in bulk samples can reveal optimal markers of malignant cells and use this approach to identify a core set of genes that is consistently expressed by astrocytoma truncal clones, including AKR1C3, whose expression is associated with poor outcomes in several types of cancer. In summary, MOMA provides a robust and flexible strategy for precisely deconstructing intratumoral heterogeneity and clarifying the core molecular properties of distinct cellular populations in solid tumors.
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The human brain expresses thousands of different long noncoding RNAs (lncRNAs), and aberrant expression of specific lncRNAs has been associated with cognitive and psychiatric disorders. While a growing number of lncRNAs are now known to regulate neural cell development and function, relatively few have been shown to underlie animal behavior, particularly with genetic strategies that establish lncRNA function in trans. Pnky is an evolutionarily conserved, neural lncRNA that regulates brain development. Using mouse genetic strategies, we show that Pnky has sex-specific roles in mouse behavior and that this lncRNA underlies specific behavior by functioning in trans. Male Pnky-knockout (KO) mice have deficits in cued fear recall, a type of Pavlovian associative memory. In female Pnky-KO mice, the acoustic startle response (ASR) is increased and accompanied by a decrease in prepulse inhibition (PPI), both of which are behaviors altered in affective disorders. Remarkably, expression of Pnky from a bacterial artificial chromosome (BAC) transgene reverses the ASR phenotype of female Pnky-KO mice, demonstrating that Pnky underlies specific animal behavior by functioning in trans. More broadly, these data provide genetic evidence that a lncRNA gene and its function in trans can play a key role in the behavior of adult mammals, contributing fundamental knowledge to our growing understanding of the association between specific lncRNAs and disorders of cognition and mood.